subgenus of Crisina, from which it differs in possessing a simple median series of apertures on the obverse face. The fact that it is not always easy to distinguish this series as composed of apertures distinct from the most median apertures of the lateral series shows the artificiality of the genus. This point is well exemplified in von Hagenow's figure of T. dorsata (von Hagenow).

TERVIA DORSATA (von Hagenow).

Plate I., fig. 8.

1851. Idmonea dorsata, von. Hagenow, Bry. Maastr. kr., p. 31, pl. ii.,

fig. 10.

Zoarium subcylindrical or triangular or flattened in a plane parallel to the obverse and reverse faces; without dorsal processes; reverse face flat or concave; zoœcia three or four in a lateral series, immersed but the boundaries are clearly marked; the distance between the different series of apertures is one and a half to two and a half times the diameter of an aperture; those of the same series are distant about a quarter the diameter of an aperture. This is the commonest form among the specimens of Cyclostomes from Need's Camp.

1899. Crisina (Tervia) gibbera, Gregory, Brit. Mus. Cat. Cret. Bry., vol. i., pp. 173-4, Text fig. 12.

Zoarium subcylindrical with the reverse face flat and possessing spine-like projections, bearing no zoccia, termed by Gregory "dorsal processes"; zoccia about three in a lateral series, immersed, but the boundaries are just shown; distance between the different series of apertures three to four times the diameter of an aperture; those of the same series distant about one-half the diameter of an aperture. Only two specimens have been found among the material here described.

Distribution. Senonian.

TERVIA DECURRENS (Pocta).

1892. Idmonea decurrens, Pocta, Mech. koryc. Hory.; Ceska. Ak. Fr. Jos. Pratze, sect. 2, p. 18, pl. ii., figs. 3-6.

Zoarium subtriangular in cross-section and flat on the reverse side; the zoœcia are immersed with their boundaries apparent; apertures

two or three in a lateral series; those of different series distant four or five diameters of an aperture, those of the same series two to three diameters of an aperture.

A single specimen is somewhat doubtfully referred to this species. It is the proximal end of a zoarium, though the first few zoœcia appear to be missing. Beginning as a thin, cylindrical branch, the zoarium rapidly widens and becomes compressed in a plane parallel to the obverse and reverse faces, at the same time becoming very curved, so that in a section along the proximal-distal axis the obverse face appears convex and the reverse face concave. When the breadth of the zoarium has reached about one-third of its length, it divides into two subcylindrical branches; one of these is broken off short, but the other continues for about 1.5 mm., without altering in shape. It would be interesting to know if on further growth the branches flatten and widen, thus recapitulating the growth stages of the first part of the zoarium; or whether the first part is really an encrusting portion, whose support has decayed, which has thrown up cylindrical branches in the same way as a Phalangella-like base has been shown by Gregory † to throw up branches of the genus Crisina. The general zoœecial characters are those of Tervia decurrens (Pocta), in which species it is provisionally placed.

*

ENTALOPHORIDE.

GENUS ENTALOPHORA, Lamouroux.

ENTALOPHORA VIRGULA (von Hagenow).

Plate I., fig. 10.

1840. Ceriopora virgula, von Hagenow, Mon. Rüg.: Neu. Jahrb., 1840, p. 646.

1851. Pustulipora virgula, von Hagenow, Bry. Maastr. kreide., p. 17, pl. i., fig. 3.

Zoarium consisting of smooth cylindrical branches; the apertures are irregularly distributed on the zoarium and are very far apart, their distance apart in a proximal-distal direction being generally more than four times the diameter of an aperture. There are never more than two apertures in the breadth of a branch. The zoœcia

* See W. D. Lang, Geol. Mag., 1905, pp. 259-260.

J. W. Gregory, Brit. Mus. Cat. Cret. Bry., vol. i., 1899, p. 159, text-fig. 11.

*

are immersed. Entalophora Pergensi, Gregory, which the above definition would also include, has thinner branches and the apertures still further apart than in E. virgula.

This is the commonest species of Cretaceous Entalophora and has been found in most of the localities whence Cretaceous Polyzoa have been recorded; but only one specimen has been found among the material here described.

Distribution. Neocomian-Danian.

ENTALOPHORA CONJUGATA, von Reuss.
Plate I., fig. 11.

1872-3. Entalophora conjugata, von Reuss, Bry. unt. Quad. Palæontogr., vol. xx., part. i., p. 117, pl. xxix., fig. 8.

Zoarium consisting of cylindrical branches; the apertures are distant from one another in a proximal-distal direction more than four times the diameter of an aperture; the apertures occur in rows of two or three across the branch; the zoœecia are immersed and their boundaries may be faintly marked. This form is very like E. geminata (von Hagenow), but the zooccia are shorter, the boundaries of the zooecia are less clearly marked, and the apertures occur in groups of three instead of two as in E. geminata. A single specimen of this species occurs among the material here described. Distribution. Cenomanian.

ENTALOPHORA ECHINATA (Römer).
Plate I., fig. 12.

1840. Pustulopora echinata, Römer, Verst. Nordd. kr., p. 22, pl. v., fig. 23.

1846. Pustulopora echinata, von. Reuss., Verst. Böhm kr., p. 64, pl. xiv., fig. 4.

Zoarium consisting of cylindrical branches; the apertures are distant from one another in a proximal-distal direction about four diameters of an aperture. There are about four apertures in the breadth of a branch; the diameter of the apertures is about 2 mm.; the zoœcia are immersed, with their boundaries more or less apparent. This species is very nearly allied to E. madreporacea (Goldfuss), from which it differs in having the apertures slightly further apart in a proximal-distal direction, the zoœcial boundaries more prominent,

J. W. Gregory, Brit. Mus. Cat. Cret. Bry., vol. i., 1899, p. 226, pl. x., figs. 5, 6, 7.

† Pustulipora geminata, von Hagenow, Bry. Maas. kr., 1851, pl. i., fig. 11, p. 20.

and the apertures less regularly arranged. The peristomes, too, are higher; but in the three specimens of this species among the material here described the peristomes are worn.

Distribution. Cenomanian to Danian.

ENTALOPHORA MADREPORACEA (Goldfuss).

Plate I., fig. 14.

1827. Ceriopora madreporacea, Goldfuss, Petref. Germ., p. 35, pl. x., figs. 12a and b.

1851. Pustulipora madreporacea, von. Hagenow, Bry. Maastr. kr., p. 18, pl. i., fig. 8.

Zoarium consisting of cylindrical branches; the apertures are distant from one another in a proximal-distal direction less than four diameters of an aperture; there are four to six apertures in the breadth of a branch; the apertures are somewhat irregularly arranged in spirals; the zoocia are immersed. Three ill-preserved specimens from among the East London material are doubtfully referred to this species. All are very short fragments of stout branches, and, in so far as the zoocial characters can be determined, resemble E. madreporacea more closely than any other form.

GENUS SPIROPORA, Lamouroux.

Spiropora should probably be united with Entalophora, for in many species of the latter genus the apertures are arranged spirally. Spiropora, however, may be defined as resembling Entalophora, but the apertures are arranged in whorls, or, if in spirals, these are very much looser than in Entalophora.

SPIROPORA VERTICILLATA (Goldfuss).
Plate I., fig. 13.

1827. Ceriopora verticillata, Goldfuss, Petref. Germ., vol. i., p. 36, pl. xi., fig. 1.

1851. Cricopora verticillata, von Hagenow, Bry. Maastr. kr., p. 20, pl. i., fig. 12.

Zoarium consisting of cylindrical branches, having the apertures arranged in whorls; there are five to ten apertures in the breadth of a branch; the whorls are distant four or five diameters of an aperture; the distance between the apertures of a whorl is a half or less than a half the diameter of an aperture; the zoœcia are immersed, but the

boundaries between them are clearly marked by thin ridges. Next to Tervia dorsata (von Hagenow), this is the commonest species of Cyclostome among the material here described.

Distribution. Neocomian to Danian.

ANTHOZOA.

In the Need's Camp material are several specimens of simple corals, thickly encrusted with Cheilostome Polyzoa. Transverse sections show that they belong to the genus Caryophyllia, but the species cannot be determined owing to their encrusted condition.